Internet good guy Manton Reece has made an accessible archive of all public posts on App.net.

In the final week before App.net shut down, I whipped up a few scripts to download every post on the platform via the API. After that finished, I also attempted to download small versions of many of the photos, but ran out of time.
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Why did I bother? At a high level, see my post from 2012 called Permanence. I also hoped to build a tool that would let anyone export their personal archive, or even migrate it to a blogging platform like Micro.blog.

I was able to see that my first post on App.net was on December 29, 2012:

This year's "best of" episode of Tech News Today was one of the most fun clip shows I've wet seen. Good job, guys.

I sent a total of 3.060 messages there and my last one was on May 2o, 2015:

Ad Blocking Is On The Rise birchtree.me

Which is an automated post from my blog through a service called PourOver, which of course doesn't work anymore. I have half a mind to build a basic HTML page to let you seach for your own archive, but I'm not sure how useful that is.